How Many Hours Must Bulbs Burn to Save $73 Million Annually?

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The discussion revolves around an advertisement claiming that replacing a 60W incandescent bulb with a 13W fluorescent bulb can save Canadian households a total of $73 million annually. Participants seek clarification on how many hours per day both bulbs need to be used to realize this savings. The average cost of electricity in Canada is noted as 8.0 cents per kW-hr, and there are approximately 13.3 million residential households. The conversation emphasizes the need to understand the conditions under which the savings can be achieved. The thread is currently closed to further contributions as it is a homework question.
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Homework Statement


An advertisement claims a total annual savings in electricity worth 73 million dollars for each Canadian household replacing one 60W incandescent bulb with an equivalent 13W fluorescent bulb. If the typical total cost of electricity (averaged across Canada) is 8.0 cents per kW-hr, how many hours per day must the replacement and original light bulb be left switched on (on average over the year)?Use the following assumptions: there are 13.3 million residential households in Canada

Homework Equations

The Attempt at a Solution


I need some help understanding the question:
"how many hours per day must the replacement and original light bulb be left switched on (on average over the year)?" ... in order to achieve what?
 
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theone said:

Homework Statement


An advertisement claims a total annual savings in electricity worth 73 million dollars for each Canadian household replacing one 60W incandescent bulb with an equivalent 13W fluorescent bulb. If the typical total cost of electricity (averaged across Canada) is 8.0 cents per kW-hr, how many hours per day must the replacement and original light bulb be left switched on (on average over the year)?Use the following assumptions: there are 13.3 million residential households in Canada

Homework Equations

The Attempt at a Solution


I need some help understanding the question:
"how many hours per day must the replacement and original light bulb be left switched on (on average over the year)?" ... in order to achieve what?
In order that powering the lower wattage bulb will cost $73mil less than for powering the higher wattage bulb----for the same number of hours.
 
Thread temporarily closed to further help, being a homework question with no working.

theone should PM me if there is more to be added to this thread
 

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